Wireless Landline unstable and no Telkom person to come check as they promised they would.

I got a wireless Telkom landline phone a couple of years ago, and I can’t get it to work. It’s unstable and complicated. I just want a simple landline for security. Each time I take it into the shop they get it to ring. Each time I bring it home it doesn’t. I logged a complaint I just got an email it is resolved. Except it isn’t I need someone to come here and sort it out.